Exhibit 10.15


 


CANCER PREVENTION PHARMACEUTICALS,
INC.


 


AMENDMENT TO VOTING AGREEMENT


 


This Amendment to Voting
Agreement (“Amendment”) is made as of September 27, 2012 by and between Cancer Prevention Pharmaceuticals, Inc., a
Delaware corporation (the “Company”) and the undersigned Investors and Founders. Capitalized terms used but not otherwise
defined herein shall have the meanings assigned to such terms in that certain Voting Agreement dated as of September 17, 2012 between
the Company and the Investors and Founders (the “Agreement”).


 


WHEREAS, together, the
undersigned Investors and Founders and the Company are authorized and desire to amend the Agreement in the manner herein provided.


 


NOW THEREFORE, in consideration
of the mutual covenants, promises and agreements of the Company and the undersigned Investors and other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties hereby agree as follows:


 


		1.	Amendment of Agreement. The Company and the undersigned Investors hereby amend the Agreement
in the manner set forth herein. Except as specifically provided herein, the terms of the Agreement shall remain in full force and
effect.



 


		2.	Recitals.



 


		A.	Recitals B, C, and D are hereby amended to read as follows:



 


B.          Certain holders (“Note
Holders”) of the Company’s Convertible Promissory Notes (“Notes”) are desirous of converting,
or have converted, the principal amount of and accrued interest on the Notes into the Company’s Series A-1 Convertible Preferred
Stock (“Series A-1 Preferred”) in accordance with the terms of the Series A-1 Preferred Stock Purchase Agreement of
the holders of such Notes (the “Conversion”).


 


C.           The Company proposes to
sell (“Financing”) of its Series A-2 Convertible Preferred Stock (“Series A-2 Preferred”
together with Series A-1 Preferred, “Series A Preferred”) to the purchasers identified on Series A-2 Preferred
Stock Purchase Agreement (the “Purchase Agreement”).


 


D.          The Investors are, or
will be, either (i) former Note Holders which have been converted pursuant to the Conversion or (ii) purchasers of Series A-2 Preferred
listed in the Purchase Agreement.


 


		B.	The following Recital E is hereby added:



 


E.          As a condition to the
Financing and the Conversion, the Parties have agreed to enter into this Agreement. 


 




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		3.	Section 5.12 Amendment. Section 5.12 is hereby amended to read as follows:



 


5.12Amendment.
Except as expressly provided herein, neither this Agreement nor any term hereof may be amended, waived, discharged or terminated
other than by a written instrument referencing this Agreement and signed by (i) the Company, (ii) Founders (who are then
employed by the Company) holding a majority of the Common Stock (determined on an as-converted basis) held by all Founders and
(iii) Investors holding a majority of the Common Stock (determined on an as-converted basis) held by all Investors; provided,
however, that Investors purchasing Shares under the Purchase Agreement after the Initial Closing (as defined in the Purchase Agreement)
may become parties to this Agreement without any amendment of this Agreement pursuant to this paragraph or any consent or approval
of any other Voting Party; and provided, further, that if any amendment, waiver, discharge or termination operates in a manner
that treats any Investor different from other Investors the consent of such Investor shall also be required for such amendment,
waiver, discharge or termination. Any such amendment, waiver, discharge or termination effected in accordance with this paragraph
shall be binding upon each Voting Party that has entered into this voting agreement. Each Voting Party acknowledges that by the
operation of this paragraph, the holders of a majority of the Common Stock (determined on an as-converted basis) held by all Founders
(who are then employed by the Company) and the holders of a majority of the Common Stock (determined on an as-converted basis)
held by all Investors will have the right and power to diminish or eliminate all rights of such Voting Party under this Agreement.


 


The parties are signing this Amendment to
Voting Agreement as of the date stated in the introductory clause.


 


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blank)


 




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Signature page to Amendment to Voting
Agreement of 


Cancer Prevention Pharmaceuticals,
Inc.


 


	Cancer Prevention Pharmaceuticals, Inc.	 
	 	 	 
	By:	/s/ Jeffrey Jacob	 
	 	Jeffrey Jacob, CEO	 


  


	Stockholder	 	Signature	 	Series A-1

Preferred

Shares Held
	 	 	 	 	 
	Frank and Linda Meyskens	 	/s/ Frank Meyskens	 	61,045
	 	 	Frank Meyskens	 	 
	 	 	 	 	 
	Eugene and Sandra Gerner	 	/s/ Eugene Gerner	 	60,963
	 	 	Eugene Gerner	 	 
	 	 	 	 	 
	Jeffrey E. Jacob	 	/s/ Jeffrey Jacob	 	122,009
	 	 	Jeffrey Jacob	 	 
	 	 	 	 	 
	GDB Investments, LLP	 	/s/ Daniel Donovan	 	672,643
	 	 	Daniel Donovan	 	 
	 	 	 	 	 
	Translational Accelerator, LLC	 	/s/ Eric Tooker	 	2,021,853
	 	 	Eric Tooker	 	 


  


	Founder	 	Signature
	 	 	 
	Meyskens Pharmaceutical Investors, LLC	 	/s/ Frank Meyskens
	 	 	Frank Meyskens
	 	 	 
	Gerner Pharmaceutical Investors, LLC	 	/s/ Eugene Gerner
	 	 	Eugene Gerner
	 	 	 
	Jeffrey E. Jacob	 	/s/ Jeffrey Jacob
	 	 	Jeffrey Jacob
	 	 	 
	Tierney Family Trust	 	/s/
    Thomas Tierney
	 	 	Thomas Tierney


 




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